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Khan N, Awasthi G, Das A. How can the complex epidemiology of malaria in India impact its elimination? Trends Parasitol 2023; 39:432-444. [PMID: 37031071 PMCID: PMC10175201 DOI: 10.1016/j.pt.2023.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 03/04/2023] [Accepted: 03/10/2023] [Indexed: 04/10/2023]
Abstract
Malaria is a human health hazard in the tropical and subtropical zones of the globe and is poised to be eliminated by the year 2030. Despite a decrease in incidence in the past two decades, many endemic countries, including India, report cases regularly. The epidemiology of malaria in India is unique owing to several features of the Plasmodium parasites, Anopheles vectors, ecoepidemiological situations conducive to disease transmission, and susceptible humans living in rural and forested areas. Limitations in public health reach, and poor health-seeking behaviour of vulnerable populations living in hard-to-reach areas, add to the problem. We bring all of these factors together in a comprehensive framework and opine that, in spite of complexities, targeted elimination of malaria in India is achievable with planned programmatic approaches.
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Affiliation(s)
- Nikhat Khan
- Molecular Epidemiology Laboratory, ICMR-National Institute of Research in Tribal Health, Jabalpur, India
| | | | - Aparup Das
- Molecular Epidemiology Laboratory, ICMR-National Institute of Research in Tribal Health, Jabalpur, India.
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2
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Rougeron V, Boundenga L, Arnathau C, Durand P, Renaud F, Prugnolle F. A population genetic perspective on the origin, spread and adaptation of the human malaria agents Plasmodium falciparum and Plasmodium vivax. FEMS Microbiol Rev 2021; 46:6373923. [PMID: 34550355 DOI: 10.1093/femsre/fuab047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 09/06/2021] [Indexed: 01/20/2023] Open
Abstract
Malaria is considered one of the most important scourges that humanity has faced during its history, being responsible every year for numerous deaths worldwide. The disease is caused by protozoan parasites, among which two species are responsible of the majority of the burden, Plasmodium falciparum and Plasmodium vivax. For these two parasite species, the questions of their origin (how and when they appeared in humans), of their spread throughout the world, as well as how they have adapted to humans have long been of interest to the scientific community. Here, we review the current knowledge that has accumulated on these different questions, thanks in particular to the analysis of the genetic and genomic variability of these parasites and comparison with related Plasmodium species infecting other host species (like non-human primates). In this paper we review the existing body of knowledge, including current research dealing with these questions, focusing particularly on genetic analysis and genomic variability of these parasites and comparison with related Plasmodium species infecting other species of host (such as non-human primates).
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Affiliation(s)
- Virginie Rougeron
- Laboratory MIVEGEC, University of Montpellier, CNRS, IRD, 900 rue Jean François Breton, 34090 Montpellier, France.,CREES, Centre de Recherches en Écologie et Évolution de la Santé, Montpellier, France
| | - Larson Boundenga
- CIRMF, Centre Interdisciplinaire de Recherches Médicales de Franceville, Franceville, Gabon
| | - Céline Arnathau
- Laboratory MIVEGEC, University of Montpellier, CNRS, IRD, 900 rue Jean François Breton, 34090 Montpellier, France.,CREES, Centre de Recherches en Écologie et Évolution de la Santé, Montpellier, France
| | - Patrick Durand
- Laboratory MIVEGEC, University of Montpellier, CNRS, IRD, 900 rue Jean François Breton, 34090 Montpellier, France.,CREES, Centre de Recherches en Écologie et Évolution de la Santé, Montpellier, France
| | - François Renaud
- Laboratory MIVEGEC, University of Montpellier, CNRS, IRD, 900 rue Jean François Breton, 34090 Montpellier, France.,CREES, Centre de Recherches en Écologie et Évolution de la Santé, Montpellier, France
| | - Franck Prugnolle
- Laboratory MIVEGEC, University of Montpellier, CNRS, IRD, 900 rue Jean François Breton, 34090 Montpellier, France.,CREES, Centre de Recherches en Écologie et Évolution de la Santé, Montpellier, France
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3
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Dash M, Pande V, Sinha A. Putative circumsporozoite protein (CSP) of Plasmodium vivax is considerably distinct from the well-known CSP and plays a role in the protein ubiquitination pathway. Gene 2020; 721S:100024. [PMID: 32550551 PMCID: PMC7285988 DOI: 10.1016/j.gene.2019.100024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 10/21/2019] [Accepted: 11/07/2019] [Indexed: 11/29/2022]
Abstract
Amidst technical challenges which limit successful culture and genetic manipulation of P. vivax parasites, we used a computational approach to identify a critical target with evolutionary significance. The putative circumsporozoite protein on chromosome 13 of P. vivax (PvpuCSP)is distinct from the well-known vaccine candidate PfCSP. The aim of this study was to understand the role of PvpuCSP and its relatedness to the well-known CSP. The study revealed PvpuCSP as a membrane bound E3 ubiquitin ligase involved in ubiquitination. It has a species-specific tetra-peptide unit which is differentially repeated in various P. vivax strains. The PvpuCSP is different from CSP in terms of stage-specific expression and function. Since E3 ubiquitin ligases are known antimalarial drug targets targeting the proteasome pathway, PvpuCSP, with evolutionary connotation and a key role in orchestrating protein degradation in P. vivax, can be explored as a potential drug target. PvpuCSP is predicted as E3 ubiquitin ligase, a part of ubiquitination pathway. Tetra-peptide tandem repeat at C terminal of PvpuCSP is exclusive to P. vivax. Moderately expressed during all parasitic stages in host and vector Partially disordered protein with both structured domains and two distinct IDRs A transmembrane protein with highly conserved functional domain across Apicomplexa
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Affiliation(s)
- Manoswini Dash
- Division of Epidemiology and Clinical Research, ICMR-National Institute of Malaria Research, New Delhi, India
| | - Veena Pande
- Department of Biotechnology, Bhimtal Campus, Kumaun University, Nainital, Uttarakhand, India
| | - Abhinav Sinha
- Division of Epidemiology and Clinical Research, ICMR-National Institute of Malaria Research, New Delhi, India
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Shen HM, Chen SB, Wang Y, Xu B, Abe EM, Chen JH. Genome-wide scans for the identification of Plasmodium vivax genes under positive selection. Malar J 2017; 16:238. [PMID: 28587615 PMCID: PMC5461743 DOI: 10.1186/s12936-017-1882-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 05/27/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The current trend of Plasmodium vivax cases imported from Southeast Asia into China has sharply increased recently, especially from the China-Myanmar border (CMB) area. High recombination rates of P. vivax populations associated with varied transmission intensity might cause distinct local selective pressures. The information on the genetic variability of P. vivax in this area is scant. Hence, this study assessed the genetic diversity of P. vivax genome sequence in CMB area and aimed to provide information on the positive selection of new gene loci. RESULTS This study reports a genome-wide survey of P. vivax in CMB area, using blood samples from local patients to identify population-specific selective processes. The result showed that considerable genetic diversity and mean pair-wise divergence among the sequenced P. vivax isolates were higher in some important gene families. Using the standardized integrated haplotype score (|iHS|) for all SNPs in chromosomal regions with SNPs above the top 1% distribution, it was observed that the top score locus involved 356 genes and most of them are associated with red blood cell invasion and immune evasion. The XP-EHH test was also applied and some important genes associated with anti-malarial drug resistance were observed in high positive scores list. This result suggests that P. vivax in CMB area is facing more pressure to survive than any other region and this has led to the strong positive selection of genes that are associated with host-parasite interactions. CONCLUSIONS This study suggests that greater genetic diversity in P. vivax from CMB area and positive selection signals in invasion and drug resistance genes are consistent with the history of drug use during malaria elimination programme in CMB area. Furthermore, this result also demonstrates that haplotype-based detecting selection can assist the genome-wide methods to identify the determinants of P. vivax diversity.
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Affiliation(s)
- Hai-Mo Shen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology Ministry of Health, 207 Rui Jin Er Road, Shanghai, 200025, People's Republic of China
| | - Shen-Bo Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology Ministry of Health, 207 Rui Jin Er Road, Shanghai, 200025, People's Republic of China
| | - Yue Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology Ministry of Health, 207 Rui Jin Er Road, Shanghai, 200025, People's Republic of China.,Institute of Parasitic Diseases, Zhejiang Academy of Medical Sciences, Hangzhou, 310013, People's Republic of China
| | - Bin Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology Ministry of Health, 207 Rui Jin Er Road, Shanghai, 200025, People's Republic of China
| | - Eniola Michael Abe
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology Ministry of Health, 207 Rui Jin Er Road, Shanghai, 200025, People's Republic of China
| | - Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Key Laboratory of Parasite and Vector Biology Ministry of Health, 207 Rui Jin Er Road, Shanghai, 200025, People's Republic of China.
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5
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Tibayrenc M, Ayala FJ. Is Predominant Clonal Evolution a Common Evolutionary Adaptation to Parasitism in Pathogenic Parasitic Protozoa, Fungi, Bacteria, and Viruses? ADVANCES IN PARASITOLOGY 2016; 97:243-325. [PMID: 28325372 DOI: 10.1016/bs.apar.2016.08.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We propose that predominant clonal evolution (PCE) in microbial pathogens be defined as restrained recombination on an evolutionary scale, with genetic exchange scarce enough to not break the prevalent pattern of clonal population structure. The main features of PCE are (1) strong linkage disequilibrium, (2) the widespread occurrence of stable genetic clusters blurred by occasional bouts of genetic exchange ('near-clades'), (3) the existence of a "clonality threshold", beyond which recombination is efficiently countered by PCE, and near-clades irreversibly diverge. We hypothesize that the PCE features are not mainly due to natural selection but also chiefly originate from in-built genetic properties of pathogens. We show that the PCE model obtains even in microbes that have been considered as 'highly recombining', such as Neisseria meningitidis, and that some clonality features are observed even in Plasmodium, which has been long described as panmictic. Lastly, we provide evidence that PCE features are also observed in viruses, taking into account their extremely fast genetic turnover. The PCE model provides a convenient population genetic framework for any kind of micropathogen. It makes it possible to describe convenient units of analysis (clones and near-clades) for all applied studies. Due to PCE features, these units of analysis are stable in space and time, and clearly delimited. The PCE model opens up the possibility of revisiting the problem of species definition in these organisms. We hypothesize that PCE constitutes a major evolutionary strategy for protozoa, fungi, bacteria, and viruses to adapt to parasitism.
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Affiliation(s)
- M Tibayrenc
- Institut de Recherche pour le Développement, Montpellier, France
| | - F J Ayala
- University of California at Irvine, United States
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6
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Winter DJ, Pacheco MA, Vallejo AF, Schwartz RS, Arevalo-Herrera M, Herrera S, Cartwright RA, Escalante AA. Whole Genome Sequencing of Field Isolates Reveals Extensive Genetic Diversity in Plasmodium vivax from Colombia. PLoS Negl Trop Dis 2015; 9:e0004252. [PMID: 26709695 PMCID: PMC4692395 DOI: 10.1371/journal.pntd.0004252] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 10/30/2015] [Indexed: 11/24/2022] Open
Abstract
Plasmodium vivax is the most prevalent malarial species in South America and exerts a substantial burden on the populations it affects. The control and eventual elimination of P. vivax are global health priorities. Genomic research contributes to this objective by improving our understanding of the biology of P. vivax and through the development of new genetic markers that can be used to monitor efforts to reduce malaria transmission. Here we analyze whole-genome data from eight field samples from a region in Cordóba, Colombia where malaria is endemic. We find considerable genetic diversity within this population, a result that contrasts with earlier studies suggesting that P. vivax had limited diversity in the Americas. We also identify a selective sweep around a substitution known to confer resistance to sulphadoxine-pyrimethamine (SP). This is the first observation of a selective sweep for SP resistance in this species. These results indicate that P. vivax has been exposed to SP pressure even when the drug is not in use as a first line treatment for patients afflicted by this parasite. We identify multiple non-synonymous substitutions in three other genes known to be involved with drug resistance in Plasmodium species. Finally, we found extensive microsatellite polymorphisms. Using this information we developed 18 polymorphic and easy to score microsatellite loci that can be used in epidemiological investigations in South America. Although P. vivax is not as deadly as the more widely studied P. falciparum, it remains a pressing global health problem. Here we report the results of a whole-genome study of P. vivax from Cordóba, Colombia, in South America. This parasite is the most prevalent in this region. We show that the parasite population is genetically diverse, which is contrary to expectations from earlier studies from the Americas. We also find molecular evidence that resistance to an anti-malarial drug has arisen recently in this region. This selective sweep indicates that the parasite has been exposed to a drug that is not used as first-line treatment for this malaria parasite. In addition to extensive single nucleotide and microsatellite polymorphism, we report 18 new genetic loci that might be helpful for fine-scale studies of this species in the Americas.
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Affiliation(s)
- David J. Winter
- The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
- * E-mail: (DJW); (AAE)
| | - M. Andreína Pacheco
- The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
- Institute for Genomics and Evolutionary Medicine (igem), Temple University, Philadelphia, Pennsylvania, United States of America
| | | | - Rachel S. Schwartz
- The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Myriam Arevalo-Herrera
- Caucaseco Scientific Research Center, Cali, Colombia
- Faculty of Health, Universidad del Valle, Cali, Colombia
| | | | - Reed A. Cartwright
- The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
- The School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Ananias A. Escalante
- The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
- Institute for Genomics and Evolutionary Medicine (igem), Temple University, Philadelphia, Pennsylvania, United States of America
- * E-mail: (DJW); (AAE)
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7
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Affiliation(s)
- Madhavi Tripathi
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, New Delhi, India
| | - Aparup Das
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, New Delhi, India
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8
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Tyagi S, Pande V, Das A. Mitochondrial genome sequence diversity of Indian Plasmodium falciparum isolates. Mem Inst Oswaldo Cruz 2015; 109:494-8. [PMID: 25075789 PMCID: PMC4155855 DOI: 10.1590/0074-0276130531] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 03/11/2014] [Indexed: 11/22/2022] Open
Abstract
We have analysed the whole mitochondrial (mt) genome sequences (each
~6 kilo nucleotide base pairs in length) of four field isolates of the malaria
parasite Plasmodium falciparum collected from different locations
in India. Comparative genomic analyses of mt genome sequences
revealed three novel India-specific single nucleotide polymorphisms. In general, high
mt genome diversity was found in Indian P.
falciparum, at a level comparable to African isolates. A population
phylogenetic tree placed the presently sequenced Indian P. falciparum
with the global isolates, while a previously sequenced Indian isolate was an
outlier. Although this preliminary study is limited to a few numbers of isolates, the
data have provided fundamental evidence of the mt genome diversity
and evolutionary relationships of Indian P. falciparum with that of
global isolates.
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Affiliation(s)
- Suchi Tyagi
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, New Delhi, India
| | - Veena Pande
- Department of Biotechnology, Kumaun University, Nainital, India
| | - Aparup Das
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, New Delhi, India
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9
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Tyagi S, Das A. Mitochondrial population genomic analyses reveal population structure and demography of Indian Plasmodium falciparum. Mitochondrion 2015; 24:9-21. [PMID: 26149324 DOI: 10.1016/j.mito.2015.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 06/29/2015] [Accepted: 06/29/2015] [Indexed: 11/30/2022]
Abstract
Inference on the genetic diversity of Plasmodium falciparum populations could help in better management of malaria. A very recent study with mitochondrial (mt) genomes in global P. falciparum had revealed interesting evolutionary genetic patterns of Indian isolates in comparison to global ones. However, no population genetic study using the whole mt genome sequences of P. falciparum isolates collected in the entire distribution range in India has yet been performed. We herewith have analyzed 85 whole mt genomes (48 already published and 37 entirely new) sampled from eight differentially endemic Indian locations to estimate genetic diversity and infer population structure and historical demography of Indian P. falciparum. We found 19 novel Indian-specific Single Nucleotide Polymorphisms (SNPs) and 22 novel haplotypes segregating in Indian P. falciparum. Accordingly, high haplotype and nucleotide diversities were detected in Indian P. falciparum in comparison to many other global isolates. Indian P. falciparum populations were found to be moderately sub-structured with four different genetic clusters. Interestingly, group of local populations aggregate to form each cluster; while samples from Jharkhand and Odisha formed a single cluster, P. falciparum isolates from Asom formed an independent one. Similarly, Surat, Bilaspur and Betul formed a single cluster and Goa and Mangalore formed another. Interestingly, P. falciparum isolates from the two later populations were significantly genetically differentiated from isolates collected in other six Indian locations. Signature of historical population expansion was evident in five population samples, and the onset of expansion event was found to be very similar to African P. falciparum. In agreement with the previous finding, the estimated Time to Most Recent Common Ancestor (TMRCA) and the effective population size were high in Indian P. falciparum. All these genetic features of Indian P. falciparum with high mt genome diversity are somehow similar to Africa, but quite different from other Asian population samples.
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Affiliation(s)
- Suchi Tyagi
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, New Delhi, India
| | - Aparup Das
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, New Delhi, India.
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10
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Das A. The distinctive features of Indian malaria parasites. Trends Parasitol 2015; 31:83-6. [PMID: 25748059 DOI: 10.1016/j.pt.2015.01.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 01/18/2015] [Accepted: 01/20/2015] [Indexed: 11/30/2022]
Abstract
Malaria and factors driving malaria are heterogeneous in India, unlike in other countries, and the epidemiology of malaria therefore is considered 'highly complex'. This complexity is primarily attributed to several unique features of the malaria parasites, mosquito vectors, malaria-susceptible populations, and ecoclimatic variables in India. Recent research on the genetic epidemiology of Indian malaria parasites has been successful in partly unraveling the mysteries underlying these complexities.
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Affiliation(s)
- Aparup Das
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, Sector 8, Dwarka, New Delhi, India.
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11
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Barry AE, Waltmann A, Koepfli C, Barnadas C, Mueller I. Uncovering the transmission dynamics of Plasmodium vivax using population genetics. Pathog Glob Health 2015; 109:142-52. [PMID: 25891915 DOI: 10.1179/2047773215y.0000000012] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Population genetic analysis of malaria parasites has the power to reveal key insights into malaria epidemiology and transmission dynamics with the potential to deliver tools to support control and elimination efforts. Analyses of parasite genetic diversity have suggested that Plasmodium vivax populations are more genetically diverse and less structured than those of Plasmodium falciparum indicating that P. vivax may be a more ancient parasite of humans and/or less susceptible to population bottlenecks, as well as more efficient at disseminating its genes. These population genetic insights into P. vivax transmission dynamics provide an explanation for its relative resilience to control efforts. Here, we describe current knowledge on P. vivax population genetic structure, its relevance to understanding transmission patterns and relapse and how this information can inform malaria control and elimination programmes.
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Key Words
- Control,
- Elimination
- Genetic diversity,
- Genetics,
- Genomics,
- Linkage disequilibrium,
- Malaria,
- Microsatellites,
- Mitochondrial DNA,
- Plasmodium vivax,
- Population structure,
- Relapse,
- Single nucleotide polymorphisms,
- Transmission,
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12
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Gupta P, Pande V, Das A, Singh V. Genetic polymorphisms in VIR genes among Indian Plasmodium vivax populations. THE KOREAN JOURNAL OF PARASITOLOGY 2014; 52:557-64. [PMID: 25352708 PMCID: PMC4210742 DOI: 10.3347/kjp.2014.52.5.557] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 04/01/2014] [Accepted: 05/20/2014] [Indexed: 01/09/2023]
Abstract
The vir genes are antigenic genes and are considered to be possible vaccine targets. Since India is highly endemic to Plasmodium vivax, we sequenced 5 different vir genes and investigated DNA sequence variations in 93 single-clonal P. vivax isolates. High variability was observed in all the 5 vir genes; the vir 1/9 gene was highly diverged across Indian populations. The patterns of genetic diversity do not follow geographical locations, as geographically distant populations were found to be genetically similar. The results in general present complex genetic diversity patterns in India, requiring further in-depth population genetic and functional studies.
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Affiliation(s)
- Purva Gupta
- National Institute of Malaria Research, Sector-8 Dwarka, New Delhi-110077, India
| | - Veena Pande
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, 263001, India
| | - Aparup Das
- National Institute of Malaria Research, Sector-8 Dwarka, New Delhi-110077, India
| | - Vineeta Singh
- National Institute of Malaria Research, Sector-8 Dwarka, New Delhi-110077, India
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13
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Dixit J, Arunyawat U, Huong NT, Das A. Multilocus nuclear DNA markers reveal population structure and demography of Anopheles minimus. Mol Ecol 2014; 23:5599-618. [PMID: 25266341 DOI: 10.1111/mec.12943] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 09/21/2014] [Accepted: 09/22/2014] [Indexed: 01/11/2023]
Abstract
Utilization of multiple putatively neutral DNA markers for inferring evolutionary history of species population is considered to be the most robust approach. Molecular population genetic studies have been conducted in many species of Anopheles genus, but studies based on single nucleotide polymorphism (SNP) data are still very scarce. Anopheles minimus is one of the principal malaria vectors of Southeast (SE) Asia including the Northeastern (NE) India. Although population genetic studies with mitochondrial genetic variation data have been utilized to infer phylogeography of the SE Asian populations of this species, limited information on the population structure and demography of Indian An. minimus is available. We herewith have developed multilocus nuclear genetic approach with SNP markers located in X chromosome of An. minimus in eight Indian and two SE Asian population samples (121 individual mosquitoes in total) to infer population history and test several hypotheses on the phylogeography of this species. While the Thai population sample of An. minimus presented the highest nucleotide diversity, majority of the Indian samples were also fairly diverse. In general, An. minimus populations were moderately substructured in the distribution range covering SE Asia and NE India, largely falling under three distinct genetic clusters. Moreover, demographic expansion events could be detected in the majority of the presently studied populations of An. minimus. Additional DNA sequencing of the mitochondrial COII region in a subset of the samples (40 individual mosquitoes) corroborated the existing hypothesis of Indian An. minimus falling under the earlier reported mitochondrial lineage B.
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Affiliation(s)
- Jyotsana Dixit
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, Sector-8, Dwarka, New Delhi, 110077, India
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14
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Ngassa Mbenda HG, Das A. Molecular evidence of Plasmodium vivax mono and mixed malaria parasite infections in Duffy-negative native Cameroonians. PLoS One 2014; 9:e103262. [PMID: 25084090 PMCID: PMC4118857 DOI: 10.1371/journal.pone.0103262] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 06/30/2014] [Indexed: 11/18/2022] Open
Abstract
The malaria parasite Plasmodium vivax is known to be majorly endemic to Asian and Latin American countries with no or very few reports of Africans infected with this parasite. Since the human Duffy antigens act as receptors for P. vivax to invade human RBCs and Africans are generally Duffy-negative, non-endemicity of P. vivax in Africa has been attributed to this fact. However, recent reports describing P. vivax infections in Duffy-negative Africans from West and Central parts of Africa have been surfaced including a recent report on P. vivax infection in native Cameroonians. In order to know if Cameroonians living in the southern regions are also susceptible to P. vivax infection, we collected finger-prick blood samples from 485 malarial symptomatic patients in five locations and followed PCR diagnostic assays with DNA sequencing of the 18S ribosomal RNA gene. Out of the 201 malaria positive cases detected, 193 were pure P. falciparum, six pure P. vivax and two mixed parasite infections (P. falciparum + P. vivax). The eight P. vivax infected samples (six single + two mixed) were further subjected to DNA sequencing of the P. vivax multidrug resistance 1 (pvmdr1) and the P.vivax circumsporozoite (pvcsp) genes. Alignment of the eight Cameroonian pvmdr1 sequences with the reference sequence showed high sequence similarities, reconfirming P. vivax infection in all the eight patients. DNA sequencing of the pvcsp gene indicated all the eight P. vivax to be of VK247 type. Interestingly, DNA sequencing of a part of the human Duffy gene covering the promoter region in the eight P. vivax-infected Cameroonians to identify the T-33C mutation revealed all these patients as Duffy-negative. The results provide evidence of single P. vivax as well as mixed malaria parasite infection in native Cameroonians and add knowledge to the growing evidences of P. vivax infection in Duffy-negative Africans.
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Affiliation(s)
- Huguette Gaelle Ngassa Mbenda
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, Sector 8, Dwarka, New Delhi, India
| | - Aparup Das
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, Sector 8, Dwarka, New Delhi, India
- * E-mail:
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Tyagi S, Pande V, Das A. New insights into the evolutionary history of Plasmodium falciparum from mitochondrial genome sequence analyses of Indian isolates. Mol Ecol 2014; 23:2975-87. [PMID: 24845521 DOI: 10.1111/mec.12800] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 05/16/2014] [Accepted: 05/16/2014] [Indexed: 12/31/2022]
Abstract
Estimating genetic diversity and inferring the evolutionary history of Plasmodium falciparum could be helpful in understanding origin and spread of virulent and drug-resistant forms of the malaria pathogen and therefore contribute to malaria control programme. Genetic diversity of the whole mitochondrial (mt) genome of P. falciparum sampled across the major distribution ranges had been reported, but no Indian P. falciparum isolate had been analysed so far, even though India is highly endemic to P. falciparum malaria. We have sequenced the whole mt genome of 44 Indian field isolates and utilized published data set of 96 genome sequences to present global genetic diversity and to revisit the evolutionary history of P. falciparum. Indian P. falciparum presents high genetic diversity with several characteristics of ancestral populations and shares many of the genetic features with African and to some extent Papua New Guinean (PNG) isolates. Similar to African isolates, Indian P. falciparum populations have maintained high effective population size and undergone rapid expansion in the past with oldest time to the most recent common ancestor (TMRCA). Interestingly, one of the four single nucleotide polymorphisms (SNPs) that differentiates P. falciparum from P. falciparum-like isolates (infecting non-human primates in Africa) was found to be segregating in five Indian P. falciparum isolates. This SNP was in tight linkage with other two novel SNPs that were found exclusively in these five Indian isolates. The results on the mt genome sequence analyses of Indian isolates on the whole add to the current understanding on the evolutionary history of P. falciparum.
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Affiliation(s)
- Suchi Tyagi
- Evolutionary Genomics and Bioinformatics Laboratory, National Institute of Malaria Research, Sector - 8 Dwarka, New Delhi, 110077, India
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Tibayrenc M, Ayala FJ. New insights into clonality and panmixia in Plasmodium and toxoplasma. ADVANCES IN PARASITOLOGY 2014; 84:253-68. [PMID: 24480316 DOI: 10.1016/b978-0-12-800099-1.00005-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Until the 1990s, Plasmodium and Toxoplasma were widely considered to be potentially panmictic species, because they both undergo a meiotic sexual cycle in their definitive hosts. We have proposed that both parasites are able of clonal (nonrecombining) propagation, at least in some cycles. Toxoplasma was soon shown to be a paradigmatic case of clonal population structure in North American and in European cycles. But the proposal provoked an outcry in the case of Plasmodium and still appears as doubtful to many scientists. However, the existence of Plasmodium nonrecombining lines has been fully confirmed, although the origin of these lines is debatable. We discuss the current state of knowledge concerning the population structure of both parasites in the light of the recent developments of pathogen clonal evolution proposed by us and of new hypotheses presented here.
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Affiliation(s)
- Michel Tibayrenc
- Maladies Infectieuses et Vecteurs Ecologie, Génétique, Evolution et Contrôle, MIVEGEC (IRD 224-CNRS 5290-UM1-UM2), IRD Center, Montpellier, France.
| | - Francisco J Ayala
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, USA
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Rodrigues PT, Alves JMP, Santamaria AM, Calzada JE, Xayavong M, Parise M, da Silva AJ, Ferreira MU. Using mitochondrial genome sequences to track the origin of imported Plasmodium vivax infections diagnosed in the United States. Am J Trop Med Hyg 2014; 90:1102-8. [PMID: 24639297 DOI: 10.4269/ajtmh.13-0588] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Although the geographic origin of malaria cases imported into the United States can often be inferred from travel histories, these histories may be lacking or incomplete. We hypothesized that mitochondrial haplotypes could provide region-specific molecular barcodes for tracing the origin of imported Plasmodium vivax infections. An analysis of 348 mitochondrial genomes from worldwide parasites and new sequences from 69 imported malaria cases diagnosed across the United States allowed for a geographic assignment of most infections originating from the Americas, southeast Asia, east Asia, and Melanesia. However, mitochondrial lineages from Africa, south Asia, central Asia, and the Middle East, which altogether contribute the vast majority of imported malaria cases in the United States, were closely related to each other and could not be reliably assigned to their geographic origins. More mitochondrial genomes are required to characterize molecular barcodes of P. vivax from these regions.
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Affiliation(s)
- Priscila T Rodrigues
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Parasitology, Gorgas Memorial Institute of Health, Panama City, Panama; Center for Global Health, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - João Marcelo P Alves
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Parasitology, Gorgas Memorial Institute of Health, Panama City, Panama; Center for Global Health, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Ana María Santamaria
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Parasitology, Gorgas Memorial Institute of Health, Panama City, Panama; Center for Global Health, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - José E Calzada
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Parasitology, Gorgas Memorial Institute of Health, Panama City, Panama; Center for Global Health, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Maniphet Xayavong
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Parasitology, Gorgas Memorial Institute of Health, Panama City, Panama; Center for Global Health, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Monica Parise
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Parasitology, Gorgas Memorial Institute of Health, Panama City, Panama; Center for Global Health, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Alexandre J da Silva
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Parasitology, Gorgas Memorial Institute of Health, Panama City, Panama; Center for Global Health, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Marcelo U Ferreira
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Parasitology, Gorgas Memorial Institute of Health, Panama City, Panama; Center for Global Health, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
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Prajapati SK, Joshi H, Carlton JM, Rizvi MA. Neutral polymorphisms in putative housekeeping genes and tandem repeats unravels the population genetics and evolutionary history of Plasmodium vivax in India. PLoS Negl Trop Dis 2013; 7:e2425. [PMID: 24069480 PMCID: PMC3777877 DOI: 10.1371/journal.pntd.0002425] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 08/01/2013] [Indexed: 11/18/2022] Open
Abstract
The evolutionary history and age of Plasmodium vivax has been inferred as both recent and ancient by several studies, mainly using mitochondrial genome diversity. Here we address the age of P. vivax on the Indian subcontinent using selectively neutral housekeeping genes and tandem repeat loci. Analysis of ten housekeeping genes revealed a substantial number of SNPs (n = 75) from 100 P. vivax isolates collected from five geographical regions of India. Neutrality tests showed a majority of the housekeeping genes were selectively neutral, confirming the suitability of housekeeping genes for inferring the evolutionary history of P. vivax. In addition, a genetic differentiation test using housekeeping gene polymorphism data showed a lack of geographical structuring between the five regions of India. The coalescence analysis of the time to the most recent common ancestor estimate yielded an ancient TMRCA (232,228 to 303,030 years) and long-term population history (79,235 to 104,008) of extant P. vivax on the Indian subcontinent. Analysis of 18 tandem repeat loci polymorphisms showed substantial allelic diversity and heterozygosity per locus, and analysis of potential bottlenecks revealed the signature of a stable P. vivax population, further corroborating our ancient age estimates. For the first time we report a comparable evolutionary history of P. vivax inferred by nuclear genetic markers (putative housekeeping genes) to that inferred from mitochondrial genome diversity.
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Affiliation(s)
- Surendra K Prajapati
- Molecular Biology Division, National Institute of Malaria Research, New Delhi, India
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Taylor JE, Pacheco MA, Bacon DJ, Beg MA, Machado RL, Fairhurst RM, Herrera S, Kim JY, Menard D, Póvoa MM, Villegas L, Mulyanto, Snounou G, Cui L, Zeyrek FY, Escalante AA. The evolutionary history of Plasmodium vivax as inferred from mitochondrial genomes: parasite genetic diversity in the Americas. Mol Biol Evol 2013; 30:2050-64. [PMID: 23733143 PMCID: PMC3748350 DOI: 10.1093/molbev/mst104] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Plasmodium vivax is the most prevalent human malaria parasite in the Americas. Previous studies have contrasted the genetic diversity of parasite populations in the Americas with those in Asia and Oceania, concluding that New World populations exhibit low genetic diversity consistent with a recent introduction. Here we used an expanded sample of complete mitochondrial genome sequences to investigate the diversity of P. vivax in the Americas as well as in other continental populations. We show that the diversity of P. vivax in the Americas is comparable to that in Asia and Oceania, and we identify several divergent clades circulating in South America that may have resulted from independent introductions. In particular, we show that several haplotypes sampled in Venezuela and northeastern Brazil belong to a clade that diverged from the other P. vivax lineages at least 30,000 years ago, albeit not necessarily in the Americas. We propose that, unlike in Asia where human migration increases local genetic diversity, the combined effects of the geographical structure and the low incidence of vivax malaria in the Americas has resulted in patterns of low local but high regional genetic diversity. This could explain previous views that P. vivax in the Americas has low genetic diversity because these were based on studies carried out in limited areas. Further elucidation of the complex geographical pattern of P. vivax variation will be important both for diversity assessments of genes encoding candidate vaccine antigens and in the formulation of control and surveillance measures aimed at malaria elimination.
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Affiliation(s)
- Jesse E Taylor
- Center for Evolutionary Medicine and Informatics, The Biodesign Institute, Arizona State University, USA
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Carlton JM, Das A, Escalante AA. Genomics, population genetics and evolutionary history of Plasmodium vivax. ADVANCES IN PARASITOLOGY 2013; 81:203-22. [PMID: 23384624 DOI: 10.1016/b978-0-12-407826-0.00005-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Plasmodium vivax is part of a highly diverse clade that includes several Plasmodium species found in nonhuman primates from Southeast Asia. The diversity of primate malarias in Asia is staggering; nevertheless, their origin was relatively recent in the evolution of Plasmodium. We discuss how humans acquired the lineage leading to P. vivax from a nonhuman primate determined by the complex geological processes that took place in Southeast Asia during the last few million years. We conclude that widespread population genomic investigations are needed in order to understand the demographic processes involved in the expansion of P. vivax in the human populations. India represents one of the few countries with widespread vivax malaria. Earlier studies have indicated high genetic polymorphism at antigenic loci and no evidence for geographic structuring. However, new studies using genetic markers in selectively neutral genetic regions indicate that Indian P. vivax presents complex evolutionary history but possesses features consistent with being part of the ancestral distribution range of this species. Such studies are possible due to the availability of the first P. vivax genome sequences. Next generation sequencing technologies are now paving the way for the sequencing of more P. vivax genomes that will dramatically increase our understanding of the unique biology of this species.
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Affiliation(s)
- Jane M Carlton
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, USA.
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Chittoria A, Mohanty S, Jaiswal YK, Das A. Natural selection mediated association of the Duffy (FY) gene polymorphisms with Plasmodium vivax malaria in India. PLoS One 2012; 7:e45219. [PMID: 23028857 PMCID: PMC3448599 DOI: 10.1371/journal.pone.0045219] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 08/14/2012] [Indexed: 11/22/2022] Open
Abstract
The Duffy (Fy) antigens act as receptors for chemokines as well as for Plasmodium vivax to invade human RBCs. A recent study has correlated the occurrence of the FY*A allele of Duffy gene with decreased susceptibility to vivax malaria, but no epidemiological correlation between the distribution of FY*A allele and incidences of vivax malaria has been established so far. Furthermore, if such correlations exist, whether natural selection has mediated the association, is an important question. Since India is highly endemic to P. vivax malaria with variable eco-climatic and varying vivax malaria epidemiology across different regions, such a question could well be answered in Indians. For this, we have genotyped the FY gene at the −33rd and the 125th nucleotide positions in 250 Indians sampled from six different zonal plus one tribal population covering the whole of India and studied possible correlations with eco-climatic and vivax malaria incidences. No FY*O allele was found, however, both the FY*A and FY*B alleles forming FY*A/FY*A, FY*A/FY*B and FY*B/FY*B genotypes were widely distributed among Indians. Five out of seven population samples significantly deviated from the Hardy-Weinberg equilibrium expectation, and two alleles (FY*A and FY*B) and the homozygote genotype, FY*B/FY*B were clinally distributed over the population coordinates. Furthermore, vivax malaria incidences over the past five years were significantly negatively and positively associated with the frequencies of the FY*A and FY*B alleles, respectively. The Northern Indians were highly differentiated from the other zonal population samples at the FY gene, as evidenced from the reconstructed Neighbor-Joining phylogenetic tree. The results specify the role of natural selection in the distribution of FY gene polymorphism in India. Furthermore, the hypotheses on the part of the FY*A allele in conferring protection to vivax malaria could be validated following population genetic studies in a vivax malaria epidemiological setting, such as India.
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Affiliation(s)
- Anita Chittoria
- Division of Genomics and Bioinformatics, National Institute of Malaria Research, New Delhi, India
| | - Sujata Mohanty
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida, Uttar Pardesh, India
| | - Yogesh Kumar Jaiswal
- School of Studies in Biotechnology, Jiwaji University, Gwalior, Madhya Pradesh, India
| | - Aparup Das
- Division of Genomics and Bioinformatics, National Institute of Malaria Research, New Delhi, India
- * E-mail:
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Khan N, Chittoria A, Pande V, Jaiswal YK, Das A. Development of multilocus putatively neutral DNA markers in the X-chromosome for population genetic studies in humans. Ann Hum Biol 2012; 39:281-9. [PMID: 22656191 DOI: 10.3109/03014460.2012.689326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND It has now been well documented that the type (coding, non-coding) and location (nuclear, mitochondrial etc.) of genetic markers heavily influence evolutionary inferences; realistic assumptions can be drawn if multiple putatively neutral DNA fragments spread across the genome are used. AIM To infer human population history, Single Nucleotide Polymorphisms (SNPs), located in the non-coding regions of different genes in the X-chromosome have been developed as 'putatively neutral markers'. SUBJECTS AND METHODS A population sample consisting of 16 male individuals from the western part of India was utilized for sequencing eight DNA fragments located in introns of three genes (Duchenne muscular dystrophy, Factor IX and Pyruvate dehydrogenase E1 sub-unit) on the human X-chromosome. PCR amplification and DNA sequencing confirmed the polymorphic status of all the fragments. RESULTS Twenty nine SNPs were found to be segregating in the Western Indian population samples. Using these SNPs the nucleotide diversity and demographic parameters of the Western Indian population were estimated. Several tests of neutrality ascertained that all eight fragments evolve putatively neutrally. Further, linkage disequilibrium analyses confirmed this fact. CONCLUSION All eight DNA fragments seem to bear the characteristics to be considered as 'putatively neutral genetic markers' and thus, could be utilized for inference of human population and demographic histories.
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Affiliation(s)
- Naazneen Khan
- Evolutionary Genomics and Bioinformatics Laboratory, Division of Genomics and Bioinformatics, National Institute of Malaria Research, Sector 8, Dwarka, New Delhi - 110077, India
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Malaria in India: the center for the study of complex malaria in India. Acta Trop 2012; 121:267-73. [PMID: 22142788 DOI: 10.1016/j.actatropica.2011.11.008] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 11/14/2011] [Accepted: 11/20/2011] [Indexed: 11/23/2022]
Abstract
Malaria is a major public health problem in India and one which contributes significantly to the overall malaria burden in Southeast Asia. The National Vector Borne Disease Control Program of India reported ∼1.6 million cases and ∼1100 malaria deaths in 2009. Some experts argue that this is a serious underestimation and that the actual number of malaria cases per year is likely between 9 and 50 times greater, with an approximate 13-fold underestimation of malaria-related mortality. The difficulty in making these estimations is further exacerbated by (i) highly variable malaria eco-epidemiological profiles, (ii) the transmission and overlap of multiple Plasmodium species and Anopheles vectors, (iii) increasing antimalarial drug resistance and insecticide resistance, and (iv) the impact of climate change on each of these variables. Simply stated, the burden of malaria in India is complex. Here we describe plans for a Center for the Study of Complex Malaria in India (CSCMi), one of ten International Centers of Excellence in Malaria Research (ICEMRs) located in malarious regions of the world recently funded by the National Institute of Allergy and Infectious Diseases, National Institutes of Health. The CSCMi is a close partnership between Indian and United States scientists, and aims to address major gaps in our understanding of the complexity of malaria in India, including changing patterns of epidemiology, vector biology and control, drug resistance, and parasite genomics. We hope that such a multidisciplinary approach that integrates clinical and field studies with laboratory, molecular, and genomic methods will provide a powerful combination for malaria control and prevention in India.
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